Portable burglar-alarm.



J. M. BUTCHER.

PORTABLE BURGLAR ALARM.

APPLICATION FILED NOV 2?.

Patented Sept. 25, 1917.

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JAMES M. BUTCHER, OF CHICAGO, ILLINOIS, ASSIGNOR T0 WILLIAM L. ROHRER, 0F

. CHICAGO, ILLINOIS.

I PORTABLE BURGLAR-ALARIVI.

Specification of Letters Patent; Patented Sept, 2,5 191'? Application filed November 23, 1914. Serial No. 873,631.

To all whom it may concern: I

Be it known that I, JAMES M. Bu'ronnn, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Portable Burglar- Alarms, of which the following is a specification.

This invention relates to improvements, 1n alarms and has for its principal object to provide an improved alarm of the portable type which may be conveniently used .by travelers or otherpersons to warn them of attempted entrance into their rooms. More particularly my invention comprises an alarm adapted to be attached to the shank of a door knob and of such construction that the turning of the door knob in either direction will cause an alarmto be given. Further features relate to the means for readily assembling and adjusting the parts and to the I simplicity of structure whereby the alarm is inexpensive in cost and efiicient in operation.

Other features and objects of the invention will be set forth in the following specification taken in connection with the accompanying drawings which illustrate a specific embodiment of the invention.

In the drawings;

Figure 1 shows a front elevation of the alarm attached to a door knob shank which is shown in section;

Fig. 2 shows a side elevation of. the alarm attached to the shank of a door knob; part of the bell casing being broken away.

Fig. 3 shows a rear elevation of the alarm.

Referring to the drawings, the numeral 10 designates a bell which may be employed to give the alarm. This bell is-of a type well known in which there is an operating member which operates normally to prevent the ringing of the bell and upon the release of which the bell is permitted to ring, as I term it, continuously, that is, for a considerable period of time. A bell of this type is spring actuated and is wound up by rotating the cap portion of the bell with respect to its base, but since the bell is well known, and I do not claim any particular form of hell, I give no detailed description thereof.

The operating or check member of the standard 12.

bell is designatedby thenumeral 11 and is in the form of a spring secured to a rigid screws 14 which enter suitable threaded apertures in the rear face of the bell casing.

The standard 12 is pivoted at its upper end to the lower angularly disposed portion 15 of a clamp member 15, the pivotal connection being made by a pin 16 secured to the clamp member and engaging aslot 17 in the An enlarged aperture 18 communicates with the slot 17 and permits the standard 12 to be readily disengaged from the clamp member 15 by moving said standard upwardly until the head of the pin 16 registers with the aperture 18.

The upper extremity of the clamp member 15 is provided with an enlarged head 15 which is threaded to be engaged by the thumb screw 19 having the knurled head 20. The lower extremity of the thumb screw 19 pivotally engages a clamping shoe 21 which is provided with an arcuate surface oppositely disposed with reference to an arcuate surface 15 on the portion 15 of the clamp member. The arcuate surfaces just described are adapted to coact with the shank 22 of a door knob 23 and it will be apparent that the thumb screw 19 may be manipulated to rigidly secure the clamp member 15 to said'door knob shank.

The operating or check member 11 is actuated to ring the bell by means of an actuating member 2 1, the lower end of which is offset at 24 to enter the bell casing and contact with said operating member. The actuating member 24 is reciprocably mounted upon the clamp member 15 by means of a rectangular slot 25 which is engaged by a lug 26 formed integrally with or attached to the portion 15* of the clamp member and which is provided with overlapping ears 27 adapted to engage the outer surface of the actuating member adjacent the'slot 25. The lug 26 has a lowerplane surface 26*. which normally coacts with the lower wall of the slot 25 and the actuating member, 24 1s normally maintained in. this positron with re-.

spect' to the lug 26 by the action of the with respect to the clamp member, thereby pressing the operating member 11 down,- Wardly and permitting the bell to ring. The angular movement, otthe clamp memher with respect to the standard 12 is limited; by thelug l5, formed ontherear face of, the portion 159 011 said clamp. member.

The clamp member having been rigidly secured tothe shank ofia. door knob, it Will;' b een. that the weight of the bell. 10 will. operate to normallymaintain the standard 12 in. a vertical position, but when the shank of the door knob is turned in either direction, thistendency of the bell; l0'to maintainthe standard 12 in. a vertical positionwill operate to..cause a relative angular movement of the clamp member with respect to said standard. This angular movement, as above explained, will cause. the lug 26 tocoact with. the lower wall of the slot 25, thereby moving. the actuating. member 2%- downwardly and giving-an alarm It willibe GNElClQHt. that this devicemay be readily'attached to the shank of any d'oo-r knob. and; that. the parts thereof are very simple and easily assembled. may be adjustedwith.respect togthe standard 12 in order toregulatethe-sensi-tiveness-of' the alarm by sliding. the screws 14 in the slotsil'3j, and-ifdesired, thestandard 12 may beremoved. tron the clamp member 15in the mannerv abouedescribed;

Fromthe above-description it will be apparent that I have provided: a; convenient and efiicient. form of. alarm which may be readily attachedto the shank ofia door knob to be actuated by the rotation of thed'oorknob in either direction.

While the form shown n the drawings is. the oneno-w preferred by me, 1t Will be understoodthat I contemplate changes-in form. and arrangement of parts as circumstances may suggest: or necessity requireber for-operating said operating member, said actuating "member belng I'QClPI'OCEllO'lY' mounted on and: supported by said clampmember and arran'ged' to be actuatedbythe rotation vofsaidclamp member with respectto said standard.

2. An alarm, comprising a bell having an The bell 1O= operating member, a standard by which saidbellis carried, a clampmember .towhich the. standard is, pivoted, and an, actuating member engaging said op erating member actuating member being provided with a rectangular slot and said clamp member being provided with a part to engage said slot and support said actuating member.

An alarm, comprising a bell having an operating member, a standard by whichS said bell is carried, a clamp member to which the standard is pivotedg alnd an actuating member engaging said operating member, said actuating member being provided with a rectangular slot and saidcl'amp member be- 30 ing provided with. apart toengage said slot; and support said actuatingmember, said operating member bein adapted to maintain said actuating mem erin normal relation said clampimember:

4. In an alarm, the combination of a bel l" having an operating member, a standard by whichsaid' bell is carried, a clamp member to which said standard is pivoted and' whiclt is adapted to be securedtotthe shank of a- 0 door knob, and an actuat/ing member arranged to engagesaid operating member and recip-rocablymounted on; said; clamp menr. ber, wherebywhen said shank isrotated in eitherdirection the'wei-ght-of'said bell will tend! to -maintain said standardin a vertical position and. thereby cause-said actuatingmember to ring said bel'l,

5. In analarm, a be'l-l having an--operating member, a standard bywhich said bell is carried; a clamp member on' which the standard is pivoted, an actuatingmember engaging said operatingmember and} operatively connected to said clam-p member-- to be; operated by a relative angular movement of" said? clam-p member andi'said standard, and supporting means carried by-sa-idqcl'am-pmember for limiting the angular movement ot'sa-id standard.

6. In ana'lar-m,-a bell-having-an operating member, a standard by which said" belli is carried; a clampxmember to which the stand ard is pivoted, an actuating. member engaging said operating member, said actuating member-being -provided with a rectangu- 11 lar slot, and a lug projecting from said mounted on said clamp member to effect In testimony whereof, I have subscribed the operation of said operating member my name.

upon relative angular movement of said standard and said clamp member, and JAMES BUTCHER means to adjust said bell With respect to Witnesses:

GEO. L. WILKINSON,

said standard to regulate the operation of WILLIAM L. ROHRER.

said actuating member.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner 0! Patents.

' Washington, D. G. 

